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The absence of effective wastewater treatment technology to eliminate emerging pollutants from municipal sewage has become a pressing issue. In this study, the efficacy of a novel modified trickling filter (MTF), conventional activated sludge process (ASP) and two tertiary systems (UV and ozonation) were compared in eliminating antibiotic-resistant bacteria (ARB), antibiotic resistance genes (ARGs) and pharmaceuticals and personal care products (PPCPs) from urban sewage. MTF and ASP resulted in >1 log unit reduction in the abundance of ARB, while for ARGs, the removal was observed in the range of 0.1 to 1.7 log units. In MTF, ARGs were substantially removed in the aerobic zone compared to the anoxic zone. The relative abundance of most of the ARGs either decreased or remained unchanged during MTF and ASP operations. However, the relative abundance of most of the ARGs increased in the secondary sludge generated from ASP. The concentration of PPCPs such as atenolol, sulfamethazine, triclosan, and ranitidine was reduced by MTF by >80 %. Overall, the results indicated that MTF followed by ozonation is the most effective combination for removing emerging contaminants from municipal sewage.
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Contaminantes Ambientales , Ozono , Aguas del Alcantarillado/microbiología , Aguas Residuales/microbiología , Genes Bacterianos , Antagonistas de Receptores de Angiotensina , Antibacterianos , Inhibidores de la Enzima Convertidora de AngiotensinaRESUMEN
During the COVID-19 pandemic, wastewater surveillance was widely used to monitor temporal and geographical infection trends. Using this as a foundation, a statewide program for routine wastewater monitoring of gastrointestinal pathogens was established in Oklahoma. The results from 18 months of surveillance showed that wastewater concentrations of Salmonella, Campylobacter, and norovirus exhibit similar seasonal patterns to those observed in reported human cases (F = 4-29, p < 0.05) and that wastewater can serve as an early warning tool for increases in cases, offering between one- and two-weeks lead time. Approximately one third of outbreak alerts in wastewater correlated in time with confirmed outbreaks of Salmonella or Campylobacter and our results further indicated that several outbreaks are likely to go undetected through the traditional surveillance approach currently in place. Better understanding of the true distribution and burden of gastrointestinal infections ultimately facilitates better disease prevention and control and reduces the overall socioeconomic and healthcare related impact of these pathogens. In this respect, wastewater represents a unique opportunity for monitoring infections in real-time, without the need for individual human testing. With increasing demands for sustainable and low-cost disease surveillance, the usefulness of wastewater as a long-term method for tracking infectious disease transmission is likely to become even more pronounced.
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This study compares the performance and microbial composition of a conventional activated sludge process (ASP) with a modified trickling filter (MTF) for urban sewage treatment. MTF (2 h HRT with effluent recycling) and ASP (8 h HRT) showed >60 % removal efficiency for COD, NH3-N and PO43--P. MTF outperformed ASP in denitrification and 5 mg/L of NO3--N was detected in the effluent of MTF. The widespread distribution of nitrogen removal functional genes (amoA, nirK, nirS, napA, narG and nosZ) in MTF indicates simultaneous nitrification and denitrification (SND) as a key process controlling nitrogen removal. In addition, Miseq sequencing was used to examine the microbial community composition in MTF and ASP. The sequencing result revealed that Proteobacteria, Planctomycetes, Chloroflexi and Actinobacteriota were the dominant phyla in both MTF and ASP. Moreover, the co-occurrence of various nitrifiers, denitrifiers, aerobic denitrifiers, and ANAMMOX bacteria in MTF suggested their role in nitrogen removal.
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Microbiota , Aguas del Alcantarillado , Aguas del Alcantarillado/microbiología , Desnitrificación , Reactores Biológicos/microbiología , Nitrificación , Nitrógeno , Bacterias/genética , Aguas Residuales/químicaRESUMEN
INTRODUCTION: School teachers play an important role in instilling positive behavior changes among school children. School children at an early age group of 2-7 years face challenges and need extra support. Utilization of psychological interventions via school teachers for oral health promotion is minimal. The present study was done to determine the impact of counseling and reinforcement by school teachers on children for a follow-up period of 1 year. MATERIALS AND METHODS: A quantitative research on 58 randomly selected children for a follow-up of one year was conducted to determine the prevalence of preoperational characteristics in school children. The tools to determine characters in preoperational children consisted of classical cognitive experiments followed by behavior counseling intervention. The interventional group received reinforcement with school teachers for a follow-up of one year. RESULTS: The assessment of the three characteristics revealed a prevalence of ego centralism, centration, and lack of conservation and reversibility in 84.4%, 89.6%, and 89.6% children, respectively. A significant difference in behavior change was seen in children who received behavior counseling and reinforcement. CONCLUSION: The present study concluded that Piaget's characteristics were consistent for a follow-up period of one year.
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Several observations in the world of comparative immunology in plants, insects, fish and eventually mammals lead to the discovery of trained immunity in the early 2010's. The first demonstrations provided evidence that innate immune cells were capable of developing memory after a first encounter with some pathogens. Trained immunity in mammals was initially described in monocytes with the Bacille Calmette-Guerin vaccine (BCG) or prototypical agonists like ß-glucans. This phenomenon relies on epigenetic and metabolic modifications leading to an enhanced secretion of inflammatory cytokines when the host encounters homologous or heterologous pathogens. The objective of our research was to investigate the trained immunity, well-described in mouse and human, in other species of veterinary importance. For this purpose, we adapted an in vitro model of trained innate immunity in dogs. Blood enriched monocytes were stimulated with ß-glucans and we confirmed that it induced an increased production of pro-inflammatory and anti-microbial compounds in response to bacterial stimuli. These results constitute the first demonstration of trained immunity in dogs and confirm its signatures in other mammalian species, with an implication of cellular mechanisms similar to those described in mice and humans regarding cellular epigenetics and metabolic regulations.
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Inmunidad Innata/inmunología , Monocitos/efectos de los fármacos , beta-Glucanos/farmacología , Animales , Células Cultivadas , Citocinas/inmunología , Perros , Femenino , Factores Inmunológicos/farmacología , Masculino , Monocitos/inmunología , Fagocitosis/efectos de los fármacosRESUMEN
We report the electrochemical performance of nanostructures of Na0.66V4O10 as cathode material for rechargeable batteries. The Rietveld refinement of room-temperature X-ray diffraction pattern shows the monoclinic phase with C2/m space group. The cyclic voltammetry curves of prepared half-cells exhibit redox peaks at 3.1 and 2.6 V, which are due to two-phase transition reaction between V5+/4+ and can be assigned to the single-step deintercalation/intercalation of Na ion. We observe a good cycling stability with specific discharge capacity (measured vs Na+/Na) between 80 (±2) and 30 (±2) mAh g-1 at current densities of 3 and 50 mA g-1, respectively. The electrochemical performance of Na0.66V4O10 electrode was also tested with Li anode, which showed higher capacity but decayed faster than Na. Using density functional theory, we calculate the Na vacancy formation energies: 3.37 eV in the bulk of the material and 2.52 eV on the (100) surface, which underlines the importance of nanostructures.
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Antimicrobial resistance (AMR) is a major global concern, especially in India where the burden of infectious diseases is high and health care spending is low. Here we quantified total coliform, faecal coliforms (FC), carbapenem-resistant enteric bacteria (CRE), blaNDM-1, and three integron genes in samples collected from wastewater effluent of 12 hospitals, 12 sewage treatment plants (STPs), 20 sewer drains, and five locations along the Yamuna River in New Delhi over two seasons. Significant correlations were found between FC levels, CRE (râ¯=â¯0.903, pâ¯=â¯0.004, nâ¯=â¯49) and blaNDM-1 (râ¯=â¯0.787, pâ¯=â¯0.003, nâ¯=â¯49) concentrations across all samples. Concentrations of coliforms, CRE, blaNDM-1, int1, and int3 were highest in hospital effluents compared to other locations in both seasons. Although absolute concentration data indicate greater abundances of CRE and blaNDM-1 in the winter, normalised data indicates greater carriage of blaNDM-1 per cell in summer samples. In general, observed CRE levels were highest in surface water downstream of areas with higher population densities. Among CRE isolates (nâ¯=â¯4077), 82%, 75%, 71% and 43% of the strains from hospitals, sewer drains, river samples, and STPs, respectively, contained blaNDM-1, implying STPs have relatively fewer blaNDM-1 positive CRE in their effluents. The most common CRE isolates in the drains were Pseudomonas putida (39%) followed by Acinetobacter baumanni (20%) and Pseudomonas montelli (19%). The present scenario in New Delhi highlights the urgent need for increased coverage of appropriate waste treatment facilities across the city to reduce CRE exposures from polluted surface waters.